NetBSD/usr.sbin/arp/arp.c

408 lines
9.4 KiB
C

/*
* Copyright (c) 1984 Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Sun Microsystems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1984 Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */
#ifndef lint
/*static char sccsid[] = "from: @(#)arp.c 5.11.1.1 (Berkeley) 7/22/91";*/
static char rcsid[] = "$Id: arp.c,v 1.3 1993/08/01 18:00:27 mycroft Exp $";
#endif /* not lint */
/*
* arp - display, set, and delete arp table entries
*/
#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <errno.h>
#include <nlist.h>
#include <kvm.h>
#include <stdio.h>
#include <paths.h>
extern int errno;
main(argc, argv)
int argc;
char **argv;
{
int ch;
while ((ch = getopt(argc, argv, "adsf")) != EOF)
switch((char)ch) {
case 'a': {
char *mem = 0;
if (argc > 4)
usage();
if (argc == 4) {
mem = argv[3];
}
dump((argc >= 3) ? argv[2] : _PATH_UNIX, mem);
exit(0);
}
case 'd':
if (argc != 3)
usage();
delete(argv[2]);
exit(0);
case 's':
if (argc < 4 || argc > 7)
usage();
exit(set(argc-2, &argv[2]) ? 1 : 0);
case 'f':
if (argc != 3)
usage();
exit (file(argv[2]) ? 1 : 0);
case '?':
default:
usage();
}
if (argc != 2)
usage();
get(argv[1]);
exit(0);
}
/*
* Process a file to set standard arp entries
*/
file(name)
char *name;
{
FILE *fp;
int i, retval;
char line[100], arg[5][50], *args[5];
if ((fp = fopen(name, "r")) == NULL) {
fprintf(stderr, "arp: cannot open %s\n", name);
exit(1);
}
args[0] = &arg[0][0];
args[1] = &arg[1][0];
args[2] = &arg[2][0];
args[3] = &arg[3][0];
args[4] = &arg[4][0];
retval = 0;
while(fgets(line, 100, fp) != NULL) {
i = sscanf(line, "%s %s %s %s %s", arg[0], arg[1], arg[2],
arg[3], arg[4]);
if (i < 2) {
fprintf(stderr, "arp: bad line: %s\n", line);
retval = 1;
continue;
}
if (set(i, args))
retval = 1;
}
fclose(fp);
return (retval);
}
/*
* Set an individual arp entry
*/
set(argc, argv)
int argc;
char **argv;
{
struct arpreq ar;
struct hostent *hp;
struct sockaddr_in *sin;
u_char *ea;
int s;
char *host = argv[0], *eaddr = argv[1];
argc -= 2;
argv += 2;
bzero((caddr_t)&ar, sizeof ar);
sin = (struct sockaddr_in *)&ar.arp_pa;
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = inet_addr(host);
if (sin->sin_addr.s_addr == -1) {
if (!(hp = gethostbyname(host))) {
fprintf(stderr, "arp: %s: ", host);
herror((char *)NULL);
return (1);
}
bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
sizeof sin->sin_addr);
}
ea = (u_char *)ar.arp_ha.sa_data;
if (ether_aton(eaddr, ea))
return (1);
ar.arp_flags = ATF_PERM;
while (argc-- > 0) {
if (strncmp(argv[0], "temp", 4) == 0)
ar.arp_flags &= ~ATF_PERM;
else if (strncmp(argv[0], "pub", 3) == 0)
ar.arp_flags |= ATF_PUBL;
else if (strncmp(argv[0], "trail", 5) == 0)
ar.arp_flags |= ATF_USETRAILERS;
argv++;
}
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s < 0) {
perror("arp: socket");
exit(1);
}
if (ioctl(s, SIOCSARP, (caddr_t)&ar) < 0) {
perror(host);
exit(1);
}
close(s);
return (0);
}
/*
* Display an individual arp entry
*/
get(host)
char *host;
{
struct arpreq ar;
struct hostent *hp;
struct sockaddr_in *sin;
u_char *ea;
int s;
bzero((caddr_t)&ar, sizeof ar);
ar.arp_pa.sa_family = AF_INET;
sin = (struct sockaddr_in *)&ar.arp_pa;
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = inet_addr(host);
if (sin->sin_addr.s_addr == -1) {
if (!(hp = gethostbyname(host))) {
fprintf(stderr, "arp: %s: ", host);
herror((char *)NULL);
exit(1);
}
bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
sizeof sin->sin_addr);
}
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s < 0) {
perror("arp: socket");
exit(1);
}
if (ioctl(s, SIOCGARP, (caddr_t)&ar) < 0) {
if (errno == ENXIO)
printf("%s (%s) -- no entry\n",
host, inet_ntoa(sin->sin_addr));
else
perror("SIOCGARP");
exit(1);
}
close(s);
ea = (u_char *)ar.arp_ha.sa_data;
printf("%s (%s) at ", host, inet_ntoa(sin->sin_addr));
if (ar.arp_flags & ATF_COM)
ether_print(ea);
else
printf("(incomplete)");
if (ar.arp_flags & ATF_PERM)
printf(" permanent");
if (ar.arp_flags & ATF_PUBL)
printf(" published");
if (ar.arp_flags & ATF_USETRAILERS)
printf(" trailers");
printf("\n");
}
/*
* Delete an arp entry
*/
delete(host)
char *host;
{
struct arpreq ar;
struct hostent *hp;
struct sockaddr_in *sin;
int s;
bzero((caddr_t)&ar, sizeof ar);
ar.arp_pa.sa_family = AF_INET;
sin = (struct sockaddr_in *)&ar.arp_pa;
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = inet_addr(host);
if (sin->sin_addr.s_addr == -1) {
if (!(hp = gethostbyname(host))) {
fprintf(stderr, "arp: %s: ", host);
herror((char *)NULL);
exit(1);
}
bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
sizeof sin->sin_addr);
}
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s < 0) {
perror("arp: socket");
exit(1);
}
if (ioctl(s, SIOCDARP, (caddr_t)&ar) < 0) {
if (errno == ENXIO)
printf("%s (%s) -- no entry\n",
host, inet_ntoa(sin->sin_addr));
else
perror("SIOCDARP");
exit(1);
}
close(s);
printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr));
}
struct nlist nl[] = {
#define X_ARPTAB 0
{ "_arptab" },
#define X_ARPTAB_SIZE 1
{ "_arptab_size" },
{ "" },
};
/*
* Dump the entire arp table
*/
dump(kernel, mem)
char *kernel, *mem;
{
extern int h_errno;
struct arptab *at;
struct hostent *hp;
int bynumber, mf, arptab_size, sz;
char *host, *malloc();
off_t lseek();
if (kvm_openfiles(kernel, mem, NULL) == -1) {
fprintf(stderr, "arp: kvm_openfiles: %s\n", kvm_geterr());
exit(1);
}
if (kvm_nlist(nl) < 0 || nl[X_ARPTAB_SIZE].n_type == 0) {
fprintf(stderr, "arp: %s: bad namelist\n", kernel);
exit(1);
}
if (kvm_read((void *)(nl[X_ARPTAB_SIZE].n_value),
&arptab_size, sizeof arptab_size) == -1 ||
arptab_size <= 0 || arptab_size > 1000) {
fprintf(stderr, "arp: %s: namelist wrong\n", kernel);
exit(1);
}
sz = arptab_size * sizeof (struct arptab);
at = (struct arptab *)malloc((u_int)sz);
if (at == NULL) {
fputs("arp: can't get memory for arptab.\n", stderr);
exit(1);
}
if (kvm_read((void *)(nl[X_ARPTAB].n_value), (char *)at, sz) == -1) {
perror("arp: error reading arptab");
exit(1);
}
for (bynumber = 0; arptab_size-- > 0; at++) {
if (at->at_iaddr.s_addr == 0 || at->at_flags == 0)
continue;
if (bynumber == 0)
hp = gethostbyaddr((caddr_t)&at->at_iaddr,
sizeof at->at_iaddr, AF_INET);
else
hp = 0;
if (hp)
host = hp->h_name;
else {
host = "?";
if (h_errno == TRY_AGAIN)
bynumber = 1;
}
printf("%s (%s) at ", host, inet_ntoa(at->at_iaddr));
if (at->at_flags & ATF_COM)
ether_print(at->at_enaddr);
else
printf("(incomplete)");
if (at->at_flags & ATF_PERM)
printf(" permanent");
if (at->at_flags & ATF_PUBL)
printf(" published");
if (at->at_flags & ATF_USETRAILERS)
printf(" trailers");
printf("\n");
}
}
ether_print(cp)
u_char *cp;
{
printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]);
}
ether_aton(a, n)
char *a;
u_char *n;
{
int i, o[6];
i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2],
&o[3], &o[4], &o[5]);
if (i != 6) {
fprintf(stderr, "arp: invalid Ethernet address '%s'\n", a);
return (1);
}
for (i=0; i<6; i++)
n[i] = o[i];
return (0);
}
usage()
{
printf("usage: arp hostname\n");
printf(" arp -a [kernel] [kernel_memory]\n");
printf(" arp -d hostname\n");
printf(" arp -s hostname ether_addr [temp] [pub] [trail]\n");
printf(" arp -f filename\n");
exit(1);
}